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As part of the history of astronomy as a science, our understanding of the sky is limited to what we can see: we have only seen the spectrum narrow electromagnetic waves that we call visible light. And only in the last century we exceeded our limits, equipment scientists began to see infrared, ultraviolet, X-ray and gamma-ray spectra, writes Ars Technica.
In recent years, scientific progress has been fundamental: we have begun to see cosmic events in general without photon recording – mainly by the LIGO laboratory, which captures gravity waves. However, LIGO is not the first player in this "invisible" league. A few years earlier, the IceCube sensor, attempting to count cosmic neutrinos, began work on the South Ashigh.
True, the result of LIGO was earlier: this detector has already captured a cosmic event, when the gravitational wave signal reached the Earth with the optical signal (gamma light). It was the first time in the history of astronomy, when an event was captured in several fundamentally different media physically.
Although IceCube, The phenomenon of high energy neutrinos is already in the collection of recorded signals, scientists have not been able to link them at specific sources of photons, but the situation changed completely yesterday: for the first time, a high-energy neutrino signal was captured. Neutral hunting
The high energy neutrinos that arrive from space are badociated with the largest cosmic rays: where do these particles of phenomenal energy come from? They can be millions of times more energetic than the particles that scientists receive in the most powerful particle accelerators on Earth.
We have such thoughts about their origins, but up to now we have not identified precisely and indisputably the source of the cosmic ray. But it is very likely that these sources of radiation are also sources of high-energy neutrinos. Knowing that neutrinos are free, we conclude that they can not accelerate alone.
Therefore, they are emitted during the decomposition of some other high energy particles, also inheriting some of their energy. Which means that the recording of peta-electron tensions is a trace of the presence of even more energetic particles. IceCube is specially designed for neutrinos identified from the space. This is an Antarctic ice cube (so named), one side of which is one kilometer long, and the sides are etched with photodetectors.
From time to time, neutrinos interact with ice atoms. If the neutrino is energetic enough, the resulting muon may have enough energy to allow the ship to travel faster than the light. In physics, such a speed is "unacceptable", so that the muon quickly loses its energy by emitting photons (what is called Cherenkov radiation). IceCube photometers record these photons, allowing scientists to know what was the energy of the "fed" neutrinos and where they came from.
Thus, in addition to the existing astronomical sensors, whose purpose is the detection of cosmic rays that pbad through our atmosphere, IceCube can also detect their source according to the neutrinos found with cosmic rays. It should also be noted that cosmic rays encountered in the Earth's atmosphere do indeed cause interference with the IceCube, as these clashes also generate muons recorded by sensors. However, they can be relatively easily distinguished – their signal reaches the detector from the outside.
Bypbading such signals and focusing entirely on the muons formed within the one kilometer ice cube, it is possible to distinguish events caused by neutrinos that migrate over great distances.
To date, IceCube has captured dozens of high-energy neutrinos and has approximately determined the direction of their origin, but so far no interesting photon sources have been found in these directions. But scientists working with this sensor have not dropped their hands and have put in place a system that, after recording the neutrinos, would provide other astronomers with approximate information about where it came from. Then, priority is given to the processes that calculate the direction information more precisely.
This system was already operational last September, when the 170922A neutrino arrived, after which a tenth warning was sent to astronomers for registration. Neutrino detectors affected about 24 volt-electronvolts (about twice as large as the "Large Hadron LHC-13 TeV" "pressed"). This means that neutrino-generated particles have a pecan-electron-volts energy level and are attributable to high-energy cosmic rays. More important this time, the neutrino came from the same cosmic side where the source of photons – the blazar TXS 0506 + 056 was already known.
Blazar is a version of a quasar-supermbadive black hole that flows to the center of the galaxy that feeds the surrounding matter. During feeding, these objects spit out jets of particles and photons that give energy to the black hole and magnetic field of its environment. On rare occasions, the orientation of the blazers is such that their discarded beaks are visible from Earth (ie we fall into their jets).
The signals emitted by blazars can change over time: black holes "twist", the volatile flow of the material that penetrates them, and therefore the energy transmitted to the depths of space fluctuates also. Subsequent observations by gamma and X-ray telescopes showed that during the neutrino recording, a period of increased activity began at TXS 0506 + 056 blazare.
Scientists evaluated previous observations of TXS 0506 + 056 and compared Blazas position information with IceCube data. They consider that in all models where increased blazar activity is badociated with neutrino production, the probability of an accidental linkage of two different sources can be ruled out by the reliability of the three standard deviations. In other words, the random overlap between the blazar and the neutron source is extremely unlikely, but not enough, so that we can call it a definitive discovery.
Not the first time?
In a separate scientific article, IceCube researchers described all previous cases of signal capture by trying to determine if it was the first time that sources of neutrinos and cosmic rays coincide – the data has accumulated for seven years. During the badysis, the total neutron background was determined and the neutron flux from TXS 0506 + 056 exceeded the background value. From 2013 to 2015, 13 neutrinos were captured on this side.
It may seem that the number is small, but when it comes to neutrinos, when the capture of each of them is in itself a serious challenge, a surplus of 3.5 standard deviations have been established. In other words, there was no definite discovery, but the discovery is very likely.
Finally, due to attempts to connect neutrinos with a blazar, a large number of telescopes appeared to target a dominant celestial sphere and swept this location into a broad electromagnetic spectrum. TXS 0506 + 056 is one of the 50 most important objects in the sky, and is one of the most important in terms of distance to the ground.
"It's more than the size of a more strident figure than the nearest blazarus," the scientists said. The observations made it possible to define the physical properties of the blazers more rigorously and to compare different models of neutrino formation: the neutrinos are formed mainly by interacting with these scattered particles, with the protons and the second, in which the neutrinos form in interaction with the electrons.
In the end, it was found that if the interactions between protons and other large particles dominated the blazarus faults, then the probability of detecting neutrinos was low – about two percent. However, if the electrons dominated, the probability of detection was simply horrible. As a result, scientists tend to conclude that TXS 0506 + 056 jets are predominantly protons and similar particles.
There is no doubt that the TXS 0506 + 056 will continue to be monitored, so in the future, we should know a lot about the properties of blazers. And IceCube project managers propose to increase the volume of ice photoconductors, thus increasing the sensitivity of the sensor. Thus, we can expect that in the future we will know much more about how the universe produces high energy particles and what conditions are needed to achieve such extreme energies.
Perhaps we find less drama in this first recording of gravitational waves than in the first, but the new "multi-media" astronomy should greatly expand our knowledge of the universe.
The details of scientific work can be found here.
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